MI5 exonerated over July 7 attacks

The Security Service has been exonerated of any blame for leaving the ringleader of the July 7 attacks free to plot the atrocities.

The Intelligence and Security Committee (ISC) analysed information held by MI5 and Special Branch about Mohammed Sidique Khan in unprecedented detail.

The MPs found counter terrorist authorities had no evidence to suspect the Leeds teaching assistant despite him crossing their radar several times.

They concluded over-stretched investigators were swamped with information as they tackled a plot to detonate fertiliser bombs at shopping centres and nightclubs.

In the long-awaited but heavily-censored second report, the committee said it "cannot criticise" decisions made by MI5.

They revealed the agency was stretched to the limit in 2004 as it emerged 54 "essential" potential terrorist targets were not being watched at all.

The committee branded the fact security bosses could only provide "reasonable" surveillance of about one in 20 terror suspects that year as "astounding".

Prime Minster Gordon Brown said the decisions that left Islamic extremist Khan free on the streets were "understandable and reasonable". He said there is no evidence to support allegations about missed clues and that the fertiliser plot, known as Operation Crevice, took precedence.

Mr Brown said: "The review shows that there is no evidence to support various allegations about clues or ignored warnings."

Campaigners renewed their plea for a full independent inquiry and accused MI5 of "running rings" around MPs and of wanting survivors to "shut up and go away".